"An air traffic control services provider shall consult those air traffic controllers who will be subject to the rostering system, or, as applicable, their representatives, during its development and its application, to identify and mitigate risks concerning fatigue which could be due to the rostering system itself."
Regulation · ATS.OR.320(b)
Consulting controllers is not a courtesy
ATS.OR.320 has two paragraphs. The first sets eight numeric elements. The second is one sentence about talking to the people the numbers apply to. Both are the same article, the same legal weight, the same enforcement.
Read the structure
Why (b) is a condition of the article, not an appendix to it
ATS.OR.320(a) lists the eight elements a rostering system has to specify: maximum consecutive duty days, maximum hours per duty, minimum rest, and the rest. ATS.OR.320(b) sits directly underneath, in the same article, with no separate heading and no softer verb. It uses "shall," the same word (a) uses for every numeric element. A provider that has picked eight defensible numbers but never consulted the controllers subject to them has not partially complied with ATS.OR.320. It has not complied with it.
This is also a deliberately European feature. ICAO's Annex 11 sets the prescriptive-versus-FRMS choice and the categories of numeric limit, but its equivalent SARP text for the prescriptive track carries no standalone duty to consult controllers before the system is built. The closest ICAO comes is inside the FRMS track, where an FRMS policy must "reflect the shared responsibility of management, air traffic controllers, and other involved personnel" ICAO Annex 11 (15th ed.), Appendix 6, §1.1.2(b) · a commitment about shared responsibility inside an approved FRMS, not a duty to consult before a prescriptive rostering system goes live. ATS.OR.320(b) applies regardless of which track the ANSP is on.
What it means in practice
Two things the article actually asks for
Consultation is ongoing, not a rollout event
The article says "during its development and its application." A rostering system that was discussed with controllers once, before launch, and never again, does not satisfy the second half of that sentence. Every subsequent change to the values behind the eight elements is itself part of the system's "application," and the same duty applies.
Consultation can run through representatives
The article reads "those air traffic controllers … or, as applicable, their representatives." An ANSP does not have to poll every controller individually; consulting the recognised union or staff representative body on the rostering system's design satisfies the same duty, provided that channel is genuine and not nominal.
EUROCONTROL's own fatigue-management guideline for rostering systems treats the consultation duty as inseparable from the scientific basis of the rules themselves, not a separate HR step:
"Training should be provided on scientific principles affecting fatigue and sleep science to support the development and implementation of a rostering system and staff consultation."
Its own conclusions repeat the same pairing as a design principle for any rostering system, not just a legal footnote: "Consultation with staff who will be subject to the rostering system, or, as applicable, their representatives, during its development and its application."EUROCONTROL, Guidelines on Fatigue Management in ATC Rostering Systems, NMD/SAF/2611, Edition 1.0, 26 April 2023, §7, p.31
What changes when it works
EASA measured the effect, not just the compliance rate
EASA's 2024 study did not only check whether ANSPs had a consultation process on paper. It asked what changed when they ran one:
"The ATCO fatigue regulatory requirements … have increased the predictability and transparency of the roster development process. This improved the motivation of the employees and allowed a better understanding of the process by the ATCO representatives and unions, thus resulting in more effective coordination."
The same study is equally direct about the failure mode: in its executive summary, ATCO representatives told the researchers that, while the formal requirements were being met, the underlying measures were "often either insufficient or ineffective in practice" EASA, Study on the Analysis, Prevention and Management of Air Traffic Controller Fatigue (D-4.C.1), May 2024, Executive Summary, p.4. A rostering system can be technically compliant with (a) and still leave (b) as a box someone ticked once.
What a rostering system has to be able to show
For consultation to be more than a meeting minute
A union representative cannot meaningfully evaluate a rostering system from a policy document alone. Annex 11 and EASA's own fatigue study both point to the same underlying need: the system itself has to produce evidence, not just a compliant-looking configuration screen.
The actual numbers, in plain language
The values chosen for all eight ATS.OR.320(a) elements, stated as numbers a non-specialist can read, not buried in a configuration export. If a rep cannot get a straight answer to "what is our maximum consecutive night duties, right now," the consultation has nothing concrete to discuss.
Evidence the limits held, and where they didn't
Annex 11 requires the State to get "evidence that the limitations are not exceeded and that non-duty period requirements are met" ICAO Annex 11 (15th ed.), §2.28.3(a). In practice that means records of planned versus actual work periods Fatigue Management Guide for Air Traffic Service Providers (CANSO/ICAO/IFATCA), §4.1.1, p.50, the same record a union representative needs to check whether the numbers agreed in consultation are the numbers actually worked.
A record of every deviation, not just the rule
Where a State allows variations from the prescriptive limits, Annex 11 requires each one to carry "the reason for the need to deviate," "the extent of the deviation," "the date and time of enactment," and "a safety case" ICAO Annex 11 (15th ed.), Appendix 5, §3. A system that cannot produce that trail for every override leaves consultation arguing about anecdotes instead of a record.
None of this is a software feature standing in for the consultation itself, the conversation still has to happen at the ANSP's table, with the union in the room. What a rostering system can do is make that conversation possible: a rule catalogue that states the current values in the open, and a record of what was actually worked against them, rather than a configuration only the vendor can read.
This page describes what the regulation requires and what makes the requirement meaningful in practice. What it looks like from a controller's or a union representative's own seat, day to day, is at the desk written for controllers and unions.